maybe there are different techniques with sub-div modelling (I've only used polygon modelling at the moment).
Though it might be wrong I know you can covert sub-d to polygons and back but I haven't tried it

I dont fully understand the last question. Do you want the wireframe to be a different colour even when viewing the filled in model? There are some settings in the general preferences somewhere that allow you to colourise the edges but I dont know exactly where - anyone know?